We will continue to measure eye torsion in different directions of gaze under a variety of circumstances, concentrating on patients with various types of strabismus before and after surgical procedures. Measurements will be derived photographically using our newly constructed optical bench and frame, allowing camera orientation along the visual axis in any direction of gaze. In addition, we will further examine the relation between torsion and convergence, torsion and head tilt, and binocular correspondence in torsion. BIBLIOGRAPHIC REFERENCES: Balliet, R. and Nakayama, K. An illusion of self rotation during voluntary eye torsion. Proc. 1977 Annual ARVO meeting. Nakayama, K., Tyler, C.W., and Appleman, J. A new angle on the vertical horopter. Proc. 1977 Annual ARVO meeting.